Installing a Honeywell rth221 Thermostat

Old 03-13-14, 06:27 PM
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Exclamation Installing a Honeywell rth221 Thermostat

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Hi, this isn't my first rodeo trying to "macguyver" things (DIY), but it seems this time I was so excited I forgot to take the precautions of writing down where everything was on the previous honeywell thermostat!

I don't know WHAT I was thinking that I didn't take a photo (dumb me!).

I do know the order of the cables and where they were hooked in my last thermostat... (I know the color order not so sure the co responding spot)

yellow -
blue -
Green -
red -R/RC

The problem is the furnace never cut on (when switched from OFF to heat and ON or AUTO).

Any help would very much be appreciated, as it is only 56 degrees in my house. Thanks
Old 03-13-14, 07:26 PM
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Welcome to the forums.

We can't guess as the wire colors aren't always used they way they should be. You can go to the furnace and locate where the thermostat wires connect to the control board. Once you've located where the wires are connected.... you can post them here.

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